The concept of inline dispensers and floating dispensers for dispensing a dispersant into a body of fluid such as a body of water is known in the art. In general, two types of dispensers exist, one for use in stagnant bodies of fluids and one for use in moving fluid streams.
An example of a floating dispenser for use in stagnant fluid such as found in an open spa, a hot tub or a swimming pool is shown in King U.S. Pat. No. 4,702,270. The floating dispenser includes an outer rotatable cylindrical housing located around a cylindrical container. To adjust the amount of dispersant released the inner housing and the outer housing are rotated with respect to one another to either increase or decrease the fluid flow area or the hole area in the side wall of the dispenser.
An example of an inline dispenser for use in dispensing materials into a moving fluid environment, such as in an inline system, is shown in U.S. Pat. No. 4,270,565. The dispenser comprises a container with openings spaced circumferentially around the bottom of the container, which is normally shielded by an outer sleeve. In operation, the container is lowered into a fluid stream to allow the fluid stream to flow directly through the container. By raising or lowering the portion of the container in contact with the fluid stream one can allow more or less of the fluid stream to flow through the container. In this type of system, one can control the release of dispersant into the inline system by controlling either the size of the fluid stream flowing through the dispenser or the velocity of the fluid stream.
In general, a user having both an inline system with a moving fluid environment and an open system with a stagnant fluid environment requires two different types of dispensers in order to controllable release the dispersant in each system. That is, one type of dispenser for the stagnant fluid environment and a second type for the inline system, which has a moving fluid environment. The present invention comprises a universal cartridge that can be adjusted to controllable release the proper amount of dispersant in either a stagnant fluid environment or a moving fluid environment.
Each of the above type of dispensing member works well when used in the proper fluid environment that it was designed for. However, it is difficult to use a dispenser, which works well in a stagnant fluid, in a moving fluid or conversely to use a dispenser, which works well in moving fluid, in a stagnant fluid and still obtain the proper dispersal rates. If one can not obtain the proper dispersal rates one can not achieve the proper concentration of the dispersant in the surrounding fluid. That is, the concentration of dispersant in the fluid may be either to high or to low. If the concentration of dispersant is a material, such as a bactericide, is to low it will not kill the bacteria in the fluid and if the concentration of the dispersant is to high it may be obnoxious or harmful. Either condition is unsatisfactory.
One of the difficulties with having a dispenser operate in either a stagnant fluid environment or in a moving fluid environment is that it appears that fluid flow conditions and, more particularly, it appears that fluid perturbations can have a substantial effect on the dispersal rate of a dispersant contained within a cartridge dispenser. Consequently, a cartridge dispenser that suitably dispenses a dispersant in a stagnant fluid environment can yield unpredictable dispersion rates when placed in a moving fluid environment even though the fluid velocity and flow rate remains the same.
Generally, the dispersant rate of a dispersant in a stagnant fluid is dependent on the difference in concentrations of the dispersant in different regions of the fluid. With a larger difference in dispersant concentrations between a dispersant in one part of the fluid and a dispersant in another part of the fluid one has a more rapid dispersant dispersal rate and with a lower difference in concentration between a dispersant in one part of the fluid and a dispersant in another part of the fluid the dispersant dispersal rate is less.
It is known that changing fluid conditions, such as changing the velocity of the fluid through a dispersant can alter the dispersant rate, i.e. the rate that a dispersant is transferred to the surrounding fluid. However, one of the problem that occurs is that if one increases the fluid velocity around a dispenser for stagnant fluids one does not always produce consistent dispensing results. That is, at one time a first velocity of fluid may produce one dispersant rate and at a later time the same fluid velocity may produce an entirely different dispersant rate. While not fully understood it is believed that fluid perturbations are present that can have a substantial effect on the dispersant dispersal rate. That is, the fluid perturbations can produce an unstable flow condition that cause the dispersant dispersal rate to fluctuate unpredictably over a wide range even though the flow rate might remain constant in the region of the dispenser.
The King Technology U.S. Pat. No. 7,059,540 discloses a universal cartridge dispenser that allows one to maintain predictable dispersant dispersal rates in either a stagnant fluid environment or a moving fluid environment when a moving fluid is directed around the universal cartridge dispenser. In the moving fluid environment one can position the universal cartridge proximate a moving fluid stream and obtain predicable results based on the dispersant transport area between the interior of the dispenser and the exterior of the dispenser. Similarly, in a stagnant fluid environment one can position the universal cartridge in a body of fluid and obtain consistent results based on the dispersant transport area in the universal cartridge dispenser. That is, it has been found that under either a stagnant fluid environment or a moving fluid environment one can effectively control the dispersant rate of the dispersant and hence the concentration of dispersant in the surrounding fluid. By allowing one to obtain a predictable and repeatable dispersant dispersal rate it allows one to use the universal cartridge dispenser in either a stagnant fluid environment or a moving fluid environment.